Filtration media, pleated media pack, filter cartridge, and methods for manufacturing

ABSTRACT

Filter media includes a filtration substrate having a first side and a second side, and constructed for filtering a fluid by flow of the fluid therethrough. The filtration substrate has a machine direction extending from a first end to a second end, and a cross direction extending from a first edge to a second edge. The filtration substrate includes a plurality of corrugations extending in the machine direction. The plurality of corrugations include a plurality of first crests formed along the first side and a plurality of second crests formed along the second side. The filtration substrate includes a plurality of bosses along the plurality of first crests or along the plurality of second crests and extending in a direction away from the other of the plurality of first crests or the plurality of second crests. Media packs, filter elements, and methods of making are provided.

This application is a continuation of U.S. application Ser. No.16/452,854, which is a continuation of U.S. application Ser. No.15/500,897, filed Jan. 31, 2017, which is a national stage applicationunder 35 U.S.C. 371 of PCT International Patent Application No.PCT/US2015/043231, filed Jul. 31, 2015, and claims priority to U.S.Provisional Application No. 62/032,395, filed Aug. 1, 2014, and U.S.Provisional Application No. 62/187,484, filed Jul. 1, 2015, the entiredisclosures of which are incorporated by reference in their entirety.

TECHNICAL FIELD

The present disclosure relates to filtration media, pleated media packs,filter cartridges, and methods for manufacturing filtration media,pleated media pack, and filter cartridges. The present disclosure isdirected to corrugated filtration media having a first side and a secondside, a plurality of first crests formed along the first side and aplurality of second crests formed along the second side, and a pluralityof bosses located along at least one of the plurality of first crests orthe plurality of second crests.

BACKGROUND

Fluid streams, such as air and liquid, carry contaminant materialtherein. In many instances, it is desired to filter some or all of thecontaminant material from the fluid stream. For example, air flowstreams to engines for motorized vehicles or for power generationequipment, gas streams to gas turbine systems, air streams to variouscombustion furnaces, and air streams to an enclosed environment carryparticulate contaminant therein that should be filtered. Also liquidstreams in the engine lubrication systems, hydraulic systems, coolantsystems, and fuel systems, can carry particulate contaminant that shouldbe filtered. It is preferred for such systems that the fluid streams arefree from select contaminant material or have the level of contaminantmaterial therein reduced. A variety of fluid filter (air or liquidfilter) arrangements have been developed for contaminant reduction.

In the case of pleated filtration media, the pleat density refers to thenumber of pleats that can be arranged in a given distance. For a givenfiltration application, there is often a desired pleat density thatmaximizes surface area of the filtration media available for filtrationand, at the same time, does not contribute to undesired pressure dropacross the pleated filtration media as a result of the pleats being tootightly arranged. In addition, it is desirable that the filtration mediadoes not “bunch” or touch because filtration media on adjacent pleatfaces that touch becomes “masked media” and masked media is generallynot available for filtration. Accordingly, the existence of maskingresults in loss of filtration surface area. An exemplary prior approachto reduce masking is to use “spacers” for separating the pleat faces. Anexemplary disclosure of “spacers” is provided in U.S. Pat. No.7,625,418.

Pleated media packs formed from corrugated filtration media aredisclosed. For example, see U.S. Pat. Publ. No. US 2006/0151382 and U.S.Pat. Publ. No. US 2010/0078379.

SUMMARY

Filter media is described that includes a filtration substrate having afirst side and a second side, and constructed for filtering a fluid byflow of the fluid therethrough from the first side to the second side orfrom the second side to the first side. The filtration substrate has afirst edge and a second edge, and a first end and a second end, whereinthe filtration substrate has a machine direction extending from thefirst end to the second end, and a cross direction extending from thefirst side to the second side. The filtration substrate includes aplurality of corrugations located in the cross direction and extendingin the machine direction. The plurality of corrugations include aplurality of first crests formed along the first side of the filtrationsubstrate and a plurality of second crests formed along the second sideof the filtration substrate. The filtration substrate includes aplurality of bosses located along the plurality of first crests or alongthe plurality of second crests and extending in a direction away fromthe other of the plurality of first crests or the plurality of secondcrests.

A filter media pack is described that includes filter media provided ina pleated configuration including alternating first and second pleattips and alternating first and second pleat faces. The filter mediaincludes a first edge and a second edge, and a width extending from thefirst edge to the second edge. The filter media includes a first end anda second end, and a length extending from the first end to the secondend. The alternating first and the second pleat tips and the alternatingfirst and second pleat faces are located along the length of the filtermedia. The filter media includes a plurality of corrugations arrangedacross the width of the media pack and extending along the length of thefilter media. The plurality of corrugations include alternating firstarcs and second arcs wherein the first arcs and the second arcs arc inopposite directions and each of the first arcs include a first crest andeach of the second arcs include a second crest. The filter mediaincludes a plurality of bosses located along the first crest of thefirst arcs or along the second crest of the second arcs so that thebosses extend in direction away from the other of the first crest or thesecond crest.

Filter elements and methods of making filter media, media packs, andfilter elements are described.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a portion of a filtration mediasubstrate in a corrugated configuration and including a plurality ofbosses according to the principles of the present disclosure.

FIG. 2 is a perspective view of a portion of the filtration mediasubstrate of FIG. 1.

FIG. 3 is a perspective view of a portion of the filtration mediasubstrate of FIG. 1.

FIG. 4 is a side view of a portion of the filtration media substrate ofFIG. 1.

FIGS. 5A and 5B are section views of the filtration media substrate ofFIG. 1 taken along lines A-A and B-B, respectively.

FIG. 6 is a perspective view of a pleated media pack of the filtrationmedia substrate of FIG. 1 showing a first flow face.

FIG. 7 is a perspective view of the filter media pack of FIG. 7 showinga second flow face.

FIG. 8 is a partial sectional view of the filtration media pack of FIG.7.

FIG. 9 is a photographic image of a sectional view of a filtration mediapack.

FIG. 10 is a photographic image of a sectional view of the filtrationmedia pack of FIG. 9.

FIG. 11 is a perspective view of an alternative filtration media packaccording to the principles of the present disclosure.

FIG. 12 is an alternative perspective view of a part of the filtrationmedia pack of FIG. 11.

FIG. 13 is a side view of the filtration media pack of FIG. 11.

FIG. 14 is a perspective view of a panel filter element containing apleated media pack.

FIG. 15 is a perspective view of a cylindrical filter element containinga pleated media pack.

FIG. 16 is a side view of the cylindrical filter element of FIG. 15.

FIG. 17 is a side view of a conical filter element containing a pleatedmedia pack.

FIG. 18 is a perspective view of a partial conical or bowed panel filterelement containing a pleated media pack.

FIG. 19 is a sectional view of the filter element of FIG. 18 taken alonglines 19-19.

DETAILED DESCRIPTION

The disclosure relates to filtration media, pleated filtration mediapacks, filter cartridges, and methods for manufacturing filtrationmedia, pleated filtration media packs, and filter cartridges. Thepleated filtration media packs can be formed by pleating the filtrationmedia. In general, filtration media can be referred to more simply as“filter media” or “media” and refers to a substrate that is used forfiltering particulate contaminants from a fluid stream. The fluid streamcan be a gas stream or a liquid stream. An exemplary gas stream includesair, and the air stream can be provided for air intake for engines formotor vehicles, power generation equipment, various combustion furnaces,HVAC, and for enclosed environments where particulates should beremoved, such as work and home environments and clean rooms. The gasstream can also be a gas stream such as a gas stream to a gas turbinesystem. Exemplary liquid streams include engine lubrication systems,hydraulic systems, coolant systems, fuel systems, and water.

The filtration media can be folded back and forth to form pleats, andthe result can be referred to as a pleated media pack. The folds in apleated media pack are often referred to as pleat tips (or pleat folds),and the pleat tips on opposite sides of the media pack typically formthe inlet flow face and the outlet flow face. The expanses of the filtermedia extending between pleat tips are often referred to as pleat faces.Pleated media packs are sometime referred to as zigzag media packsbecause the filter media is arranged in a zigzag pattern where thefilter media alternates from pleat tip to pleat face to pleat tip topleat face, etcetera.

Pleated media packs can be arranged in any desired configuration.Exemplary configurations include panel filter arrangements and closedloop or tubular filter arrangements. Panel filter configurations includepanel filters and often have an inlet flow face and an outlet flow facearranged on opposite sides of the filter cartridge so that the fluid tobe filtered enters the media pack at the inlet flow face and filteredfluid exits the media pack at the outlet flow face on the opposite sideof the media pack. Panel filters are common in situations where thefluid flows in a straight through configuration. Closed loop or tubularfilter arrangements often have an inlet flow face on an outside of themedia pack and an outlet flow face on an inside of the media pack, orvice versa. Exemplary closed loop filter arrangements includecylindrical and conical filters. Cylindrical filters and conical filtersoften have an outside flow face and an inside flow face where fluidtypically flows from an outside surface and through the filtration mediato an internal region and then out one or both of the end caps, or viceversa.

Filtration Media

Now referring to FIGS. 1-4, an exemplary filtration media or filtermedia is shown at reference number 10. The filter media 10 is shown as adiscrete sheet but it should be understood that the filter media 10 canbe considered extending almost continuously in the machine directionindicated by the arrow M. The transverse to the machine direction M isthe cross direction C or transverse direction. The filter media 10 isshown as a substrate 11 that exhibits filtration properties. Thefiltration media 10 can be referred to as a corrugated substrate 12because of the plurality of corrugations 13 extending across the filtermedia 10 from a first edge 14 to a second edge 16. The plurality ofcorrugations 13 are shown extending continuously in the machinedirection M. The number of corrugations across the filter media 10depends on the length of the cross direction C and the corrugationdensity (the number of corrugations per unit length from the first edge14 to the second edge 16). The plurality of corrugations 13 helpsprovide the filtration media 10 with strength and rigidity compared to anoncorrugated substrate of the same material.

The filter media 10 includes a first side 20, and a second side 22opposite the first side 20. The plurality of corrugations 13 can becharacterized as including a plurality of first crests 24 along thefirst side 20 of the corrugated substrate 12 and generally extending ina direction away from the second side 22, and a plurality of secondcrests 26 formed along the second side 22 and generally extending in adirection away from the first side 20. Each corrugation 13 can beconsidered as including a first crest 24 and a second crest 26. From theperspective of FIG. 1 viewing the first side 20, the plurality of secondcrests 26 can be perceived as a plurality of first troughs 28 so thatthe plurality of corrugations 13 can be considered as alternating firstcrests 24 and first troughs 28. From the perspective of FIG. 3 viewingthe second side 22, the plurality of first crests 24 can be perceived asa plurality of second troughs 30 so that the plurality of corrugations13 can be considered as alternating second crests 26 and second troughs30.

The filter media 10 includes a plurality of bosses 31. The plurality ofbosses 31 can be provided as a plurality of first bosses 32 and aplurality of second bosses 33. The plurality of first bosses 32 areprovided located along the plurality of first crests 24, and theplurality of second bosses 33 are provided located along the pluralityof second crests 26. The plurality of first bosses 32 are providedextending from a base 34 to a top 36 in a direction away from theplurality of first troughs 28. The plurality of first bosses 32 areshown extending in a direction away from the second side 22. That is,the plurality of first bosses 32 are shown projecting above theplurality of first crests 24. Referring to FIG. 5A, the plurality offirst bosses 32 are provided having a height H extending from a bossbase 34 to a boss top 36. The boss base 34 is preferably located at thecrest top 40 that forms the peak or maximum of a crest in order toachieve the most benefit of the boss height H. While the boss base 34 ispreferably located at the crest top 40, it should be understood that theboss base 34 may be offset so that it is not exactly formed at the cresttop 40 but instead may be located on the crest rise 42 proximate thecrest top 40 but not at the crest top 40. The difference in heightbetween the crest top 40 and the crest rise 42, if the boss is locatedon the crest rise 42, may result in a boss height H that is less thanthe idealized boss height which is the distance between the boss base 34and the boss top 36. Accordingly, by locating a boss on the crest rise42, it is expected that the boss height H will be less than if the bosswere located at the crest top 40.

The plurality of second bosses 33 are located along the plurality ofsecond crests 26 and are provided extending from a base 34′ to a top 36′in a direction away from the plurality of second troughs 30. Theplurality of second bosses 33 are shown extending in a direction awayfrom the first side 20. That is, the plurality of second bosses 33 areshown projecting below the plurality of second crests 26 (for example,from the perspective of FIG. 4). Referring to FIG. 5B, the plurality ofsecond bosses 33 are provided having a height H′ extending from the bossbase 34′ to the boss top 36′. The boss base 34′ is preferably located atthe crest top 40′ that forms the peak or maximum of the second crests 26in order to maximize the boss height H. While the boss base 34′ ispreferably located at the crest top 40′, it should be understood thatthe boss base 34′ may be offset so that it is not exactly formed at thecrest top 40′ but instead may be located on the crest rise 42′ proximatethe crest top 40′ but not at the crest top 40′. The difference in heightbetween the crest top 40′ and the crest rise 42′, if the boss is locatedon the crest rise 42′ may result in a boss height H′ that is less thanthe idealized boss height which is the distance between the boss base34′ and the boss top 36′. Accordingly, by locating a boss on the crestrise 42′, it is expected that the boss height H will be less than if theboss were located at the crest top 40′.

The boss height of the plurality of bosses 31 is preferably sufficientso that, when the filter media 10 is pleated, the plurality of bosses 31help prevent the pleat faces 45 from touching each other except wherethe plurality of bosses 31 touch the pleat faces 45. Accordingly, byproviding that the tops of the plurality of bosses 31 touch the opposingpleat face, the only areas of masking are the areas where the tops ofthe bosses touch the opposing pleat faces. As a result, fluid is able tomove between the pleat faces and the remainder of the pleat faces areavailable for filtration.

The filter media 10 can be prepared so that it can be folded into apleated arrangement. For the filter media 10, a score or crease 48 canbe provided separating the pleat faces. In general, the filter media 10will form a pleat tip at the score or crease 48. As shown in FIG. 1, thefilter media 10 includes two pleat faces 46 and 47 that are separated bythe score or crease 48. The length of the pleat faces 45 can be selectedas the distance between score or crease areas 48. The score or creaseareas 48 can be introduced by creating a crease in the filter media sothat the media can be folded. While forming the filter media, the filtermedia can be scored by applying an edge to the filter media supported bya backing. In particular, the scoring can occur in alternatingdirections so that the filter media can be folded conveniently in azigzag pattern.

The bosses refer to a raised region of a three dimensional projectionfrom a surface of the filter media. The bosses can also be referred toas dimples and can be created by embossing or dimpling. One techniquefor forming the bosses includes pressing the filtration media betweentwo plates so that the bosses or dimples are formed from the projectionand recesses provided in the plates. Alternatively, the bosses ordimples can be created by other techniques that generally involve adeformation of the filter media to create the bosses or dimples. Thebosses or dimples are preferably prepared in a way that does not resultin a tearing or cutting of the filtration media. The embossing ordimpling can be done after corrugating, and can be done before the wetlaid fiber has been cured. The embossing or dimpling can be done aftercuring the filter media, but it is expected that there will be a greaterlevel of spring back compared to embossing or dimpling prior to curingthe filter media.

The plurality of bosses are formed so that they extend in a directionaway from the filter media. The plurality of bosses 32 and 33 in FIG. 4are shown extending away from the filter media 10 even though theplurality of bosses 32 and 33 are actually part of the filtration media10. The phrase “in a direction away from” means that the bosses projectoutwardly from a convex surface (for example, away from thecorrugations) rather than inwardly (for example, into the corrugations).By extending away from the filter media, the bosses are available toprovide separation between adjacent pleat faces. It should also be notedthat in place of bosses, the desired separation could be achieved usingbeads of adhesive or polymer. The beads could be placed similarly to thebosses to achieve separation between adjacent sheets of media. Further,the beads could be placed to contact the adjacent sheet of media priorto the bead curing. In this example, the bead adheres to both adjacentpleat faces. Stretching of the bead could also be induced during thecuring process to cause the bead to elongate and provide additionalseparation between the adjacent sheets of media if desired. In contrast,bosses that extend toward the filtration media would not be available toprovide separation between adjacent pleat faces.

For the filtration media 10, the pleat faces 45 include a first pleatface 46 and a second pleat face 47. The length of the first pleat face46 and the second pleat face 47 correspond to the pleat depth of theresulting pleated media pack once the filtration media 10 is folded in azigzag configuration. The plurality of first bosses 32 are shownextending from the plurality of first crests 24 in the region of thefirst pleat face 46 and do not extend from the plurality of the firstcrests 24 located in the second pleat face 47. Similarly, the secondplurality of bosses 33 are shown extending from the plurality of secondcrests 26 in the second pleat face 47 but do not extend from theplurality of second crest 26 located in the first pleat face 46.Accordingly, the plurality of first bosses 32 can be located in thefirst pleat face 46 and not the second pleat face 47, and the pluralityof second bosses 33 can be provided in the second pleat face 47 and notthe first pleat face 46. As a result, when the filtration media 10 isfolded into a pleated configuration, the plurality of first bosses 32provide separation between the pleat faces 46 and 47 as a result ofextending from the pleat face 46 without also extending from the pleatface 47 that might engage the plurality of bosses 32 on the first pleatface 46. Similarly, the plurality of second bosses 33 can be providedfor separating the pleat faces 46 and 47 as a result of extended fromthe pleat face 47 without also extended from the first pleat face 46 andcontacting the plurality of second bosses 33 on the second pleat face47. If bosses exist along the same crest on opposite pleat faces,several possibilities exist. One possibility is that the bosses willengage each other thereby creating, in certain circumstances, increasedseparation which may or may not be desirable. In general, it is expectedthat with the movement of the pleat faces relative to each other, it canbe difficult to ensure that bosses on opposite pleat faces and on a samecrest will contact each other only on boss tops. It is more likely thatthe bosses would contact each other along their sides thereby increasingmasking because the masking now exist along a potentially greater areaof contact that may include the sides of the bosses as well as where thebosses touch an opposing pleat face. In addition, the increased numberof bosses may interrupt flow of fluid between the flow faces. Althoughthe pleated media 10 is shown with a plurality of first bosses 32 on thefirst on the first pleat face 46, and a plurality of second bosses 33 onthe second pleat face 47, it should be appreciated that the firstplurality of bosses 32 can be provided in both the first pleat face 46and the second pleat face 47, and the plurality of second bosses 33 canbe provided in both the first pleat face 46 and the second pleat face47, if desired. The bosses can be formed by alternately pressing thefiltration media 10 in the first pleat face 46 and the second pleat face47. For example, the plurality of first bosses 32 can be formed bypressing the first pleat face 46 from the second side 22, and theplurality of second bosses 33 can be formed in the second pleat face 47by pressing from the first side 20.

The filtration media 10 can be provided with only the plurality of firstbosses 32 or only the plurality of second bosses 33. In the case wherethe plurality of bosses extend from the plurality of first crests 24 orfrom the plurality of second crests 26, it is preferable that theplurality of bosses 32 can be arranged so that the plurality of bossesprovide separation between pleats on the downstream side of the filtermedia 10. In typical applications, the fluid to be filtered (such asair) flows from the upstream side of the filter media 10 to thedownstream side of the filter media 10. It is the flow through thefilter media 10 from the upstream side to the downstream side thatprovides for filtration. In the case of pleated media, fluid flowing tothe upstream side has a tendency to keep the pleats on the upstream sideseparated. Furthermore, this fluid flow also has a tendency to push thedownstream side of the pleats together. Accordingly, by locating theplurality of bosses on the downstream side of the filter media 10, theplurality of bosses can help keep the pleats separated. Accordingly, insuch situations, it may be possible to forego the presence of aplurality of bosses on the upstream side and only provide for thepresence of a plurality of bosses on the downstream side of the filtermedia.

It is generally recognized that when pleat faces touch each other, thelocation of the media that touches each other has a tendency to becomemasked, and masked media is generally unavailable for filtration.Accordingly, when large surfaces of filtration media touch each other,there is a tendency for the filter media to lose filtration capacity asa result of the loss of surface area available for filtration. Inaddition, the presences of masking can increase pressure drop. Byminimizing the amount of surface area that becomes masked, filtrationcapacity can be increased and pressure drop can be decreased. In thecase of corrugated filtration media that does not include a plurality ofbosses for separating pleat faces, it is expected that crests ofcorrugations will generally align with each other and, unless separated,there may be significant masking along the crests where the adjacentmedia touches each other. By introducing a plurality of bosses that havethe effect of separating the adjacent sheets of filter media, the amountof surface area lost to masking generally corresponds to the surfacearea of the boss tops 42 and the surface area of the corresponding crest(or trough) that touches the boss tops 42. Accordingly, a significantamount of masking can be decreased by utilizing a plurality of bosses toseparate adjacent sheets of filter media.

The corrugated substrate used for filtration can be characterized by theamplitude and frequency of the corrugations. In general the amplituderefers to the distance between adjacent peaks, and the frequency canrefer to the number of full corrugations per unit distance. If theamplitude is almost zero, then the filtration media can be considerednon-corrugated. When the corrugations are extending in the machinedirection, the distance in the frequency measurement is measured fromthe first edge 14 to the second edge 16. A full corrugation refers tothe combination of an adjacent first crest and first trough. The valuesof amplitude and frequency depend on the properties and chemistry of thefiltration media. It is often desirable to use cellulosic media forfiltration purposes because it is generally less expensive compared tomedia containing synthetic fibers. In general, cellulosic media isuseful for filtration in applications such as engine air filtration, gasturbine filtration, and engine liquid system filtration and typicallyhas a basis weight in a range of about 48 lb/3,000 ft² to about 75lb/3,000 ft². For such cellulosic media, and for other media containingsynthetics and/or materials in addition to cellulose (for example,cotton or other natural fibers). The amplitude can be sufficient toprovide the filtration media with increased rigidity compared withotherwise identical but non-corrugated filtration media. Further, thecorrugations can include minor corrugations or ridges within thecorrugations to add additional stiffness to the pleats. A desirableamplitude that can provide increased rigidity is at least about 5 milswherein one mil is equivalent to 0.001 inch. A desirable amplitude canbe about 150 mils or less. An exemplary range of amplitude can be about5 mils to about 150 mils. In the case of filtering air for engine intakesystems, the amplitude of the filtration media can be about 5 mils toabout 75 mils, about 10 mils to about 60 mils, and can be about 20 milsto about 50 mils. In the case of deep panels for use in systems such asgas turbine system, the corrugations can be about 60 mils to about 150mils, and can be about 80 mils to about 120 mils. The frequency can beabout 125 mils to about 1000 mils. In addition, the frequency can beabout 200 mils to about 600 mils, and can be about 250 mils to about 500mils.

The plurality of bosses are preferably provided along a crest of acorrugation and provide a sufficient height to prevent adjacent mediafrom touching and at a sufficient distribution so that the media resistsdeflection between bosses that would other cause the deflected media onadjacent sheets to touch. Preferably, the plurality of bosses areprovided along each crest of a corrugation to help maintain separationbetween pleat faces. The bosses are preferably arranged along acorrugation crest and separated by at least about 0.25 inch to providesufficient separation between adjacent bosses so that fluid can flowbetween the adjacent bosses. In addition, the bosses are preferablyspaced along a corrugation crest so that the filter media does notdeflect so that the filter media of opposing faces touch betweenadjacent bosses.

The boss spacing can be non-uniform and can vary, for example, byincreasing or decreasing the density of the bosses along the length ofthe corrugation or transversely. Further, the boss shape or height canbe non-uniform and can vary, for example, by increasing or decreasingthe height of the bosses along the length of the corrugation ortransversely. The separation can be about 0.25 inch to about 1.0 inch,and can be about 0.40 inch to about 0.85 inch. The bosses can bereferred to as projections or embossments. In general, the bosses canhave any shape that provides the desired separation effect betweenadjacent sheets of media. Further, the boss shapes can span a largerarea than spherical or truncated conical bosses. They can take onirregular shapes and can, for example, be elongated in either thelateral or transverse direction to add stiffness to the corrugation andthe pleats. Exemplary boss shapes include spherical and truncatedconical. These shapes are expected to be the least likely to tear as aresult of forming the bosses. The bosses can be formed by pressing themedia into a desired shape using, for example, a press plate. Thespherical and truncated conical shapes on the press plate can beprovided with soft edges so that they do not tear the filter media whenthe press plate is applied to the filter media. In general, the heightof the plurality of bosses should be sufficient to provide separationbetween adjacent media sheets. The boss height can be at least about 5mils (0.005 inch) in order to provide separation. If the height of aboss is less than 5 mils, then the boss may not provide sufficientseparation between adjacent sheets of filter media. Furthermore, theheight of the plurality of bosses should not be so great that it causestearing of the media during formation of the bosses. In the case ofcellulosic media having a basis weight of about 48 to 75 lb/3,000 ft²,it is expected that the boss height will be less than about 50 mils.Exemplary boss height ranges include about 5 mils to about 50 mils,about 7 mils to about 40 mils and about 10 mils to about 30 mils. Inaddition, the base of a boss can have a perimeter that is sufficient toprovide the desired boss height without tearing the media to achieve theboss height. For an exemplary conical shaped boss, the plurality ofbosses having that conical shape can have a base perimeter of about 10mils to about 60 mils. The boss top is preferably spherical in shape orprovided with an arc shape thereby avoiding hard angles that may have atendency to tear during formation of the boss.

Pleated Media Pack

Now referring to FIGS. 6-8, a portion of a pleated media pack is shownat reference number 80. The pleated media pack 80 is shown with thefilter media 82 folded back and forth upon itself in a zigzag pattern asa result of folding at the pleat tips 84 and 86. The pleat tips 84 forma first flow face 88 and the pleat tips 86 form a second flow face 90.The pleated media pack 80 can be characterized as having a volumeasymmetry because it provides a greater volume on the first pleat face88 side compared to the second pleat face 90 side. In many applications,it may be desirable to provide the side of the pleated media pack havinga greater volume as the inlet side, and provide the side of the pleatedmedia pack having the lesser volume as the outlet side. This type ofconfiguration provides for greater loading of particulates on the inletside. In general, volume asymmetry refers to one side of the media packhaving a volume that is at least 10% greater than the volume of theother side of the media pack. The upstream side refers to the volume ofthe media pack prior to filtration, and the downstream side refers tothe volume of the media pack after filtration. The volume asymmetry canbe achieved by the shape of the corrugation (for example, such as mediapack 80) or by the arrangement of the media pack (for example, acylindrical or conical media pack).

The filter media 82 can be considered a pleated form of the filter media10 shown in FIGS. 1-4 wherein the first pleat face 46 and the secondpleat face 47 form the first pleat face 92 and the second pleat face 94,respectively. As more clearly illustrated in FIG. 8, the first pleatface 92 includes a plurality of first bosses 96, and the second pleatface includes a plurality of second bosses 98.

The filter media 82 includes a plurality of corrugations 100, and thepleat tips 84 and 86 are shown folded across the plurality ofcorrugations 100. As more clearly shown in FIG. 8, the filter media 82has a first side 102 and a second side 104 and, when folded into a pleatconfiguration, the first side 102 alternatively faces upwardly anddownwardly, and the second side 104 alternately faces upwardly anddownwardly in the configuration shown in FIGS. 6-8. This is a result ofthe filter media 82 being folded back and forth upon itself In addition,the plurality of first bosses 96 are shown extending from the first side102 in a direction away from the second side 104, and the plurality ofsecond bosses 98 are shown extending from the second side 104 in adirection away from the first side 102. For the pleated media 82, theplurality of first bosses 96 are provided in the first pleat face 94 andnot in the second pleat face 96, and the plurality of second bosses 98are provided in the second pleat face 94 and not in the first pleat face92. Accordingly, the plurality of first bosses 96 and the plurality ofsecond bosses 96 are located in alternating pleat face, and are notpresent in the same pleat face in the filter media 82. It can beappreciated that the plurality of first bosses 94 and the plurality ofsecond bosses 96 can be provided in the same pleat face, if desired.

Now referring to FIGS. 9 and 10, images of a pleated filter media packare shown at reference number 110. Both images are sectional views ofthe pleated media pack 110. In the case of FIG. 9, the image shows thepleated filter media pack 110 cut through the layers of filter media 112relatively close to the plurality of bosses 114 so that the plurality ofbosses 114 are clearly shown separating the layers of filter media 112.In contrast, the image of FIG. 10 shows a cut through the pleated filtermedia pack 110 further away from the plurality of bosses 114 so that theplurality of bosses 114 are almost not visible in the image and thelayers of filter media at 112 appear to be floating in air away fromeach other.

Now referring FIGS. 11-13, an alternative pleated filter media pack isshown at reference number 150. The filter media pack 150 is formed fromfilter media 152 that is folded into a pleated configuration. The filtermedia 152 includes a plurality of corrugations 154 extending in amachine direction M. The filter media pack 150 includes first pleat tips156 and second pleat tips 158, and first pleat faces 160 and secondpleat faces 162. Also shown are bosses 164. It is pointed out that thelines 170 and 172 shown in FIGS. 11-13 represent tangent lines to helpillustrate the shape of the corrugations at the pleat tips.

The plurality of corrugations 154 can be characterized as “symmetriccorrugations” because the volume on the inlet side of the filter mediapack 150 can be considered as about the same as the volume on the outletside of the filter media pack 150. For example, the difference in volumebetween the two sides, if a difference exists, is less than 10%. Incontrast, in the case of the filter media pack shown in FIGS. 6-8, thereis a difference in volume between the inlet side and the outlet side ofthe filter media pack that is greater than 10%. The plurality ofcorrugations in FIGS. 6-8 provide the media pack 80 can be characterizedas “asymmetric corrugations.” Furthermore, although the plurality ofcorrugations 154 can be characterized as “symmetric corrugations,” themedia pack 150 can be formed into a media pack that provides volumeasymmetry by, for example, forming a cylindrical media pack.

Filtration Media Generally

The filtration media can be provided as a relatively flexible media,including a non-woven fibrous material containing cellulose fibers,synthetic fibers, glass fibers, or combinations thereof, often includinga resin therein, and sometimes treated with additional materials. Anexample filtration media can be characterized as a cellulosic filtrationmedia that can tolerate about up to twelve percent (12%) strain withouttearing when wet and warm, but which will rupture at lower percentstrain when dry and cold (as low as 3% with some media). The filtrationmedia can be corrugated, embossed, scored or creased, and folded into apleated configuration without unacceptable media damage. In addition,the filtration media is desirably of a nature such that it will maintainits corrugations, boss structure, and pleated configuration, during use.While some filtration media is available that can tolerate greater thanabout twelve percent (12%) strain, and such media can be used accordingto the invention, that type of media is typically more expensive becauseof the incorporation therein of synthetic fibers.

In the corrugating process, an inelastic deformation may be created inthe filtration thereby preventing the media from returning to itsoriginal shape. The corrugation may sometimes tend to spring partiallyback, recovering only a portion of the stretch and bending that hasoccurred. Also, the media can contain a resin. During the corrugatingprocess, the media can be heated to soften the resin. When the resincools, it will help to maintain the corrugations. The formation of thebosses can be achieved by embossing the filter media. For example, thefilter media can be placed between plates that, through pressure, createthe bosses. Similar to the corrugating process, and in elasticdeformation may be created in the filtration media thereby preventingthe media from returning to its original shape. Although the media maytend to spring back partially, the extend of the embossing should resultin a desired plurality of bosses. Furthermore, the plurality of bossescan be alternated between pleat faces so that the bosses extend inalternating directions in alternating pleat faces. That is, the bossesin a first pleat face may extend in a first direction, and the bosses inthe adjacent pleat face may extend in the opposite direction. Thispattern may continue.

Furthermore, the corrugated and embossed media may be scored or creasedat the location of the pleat tips to help when folding the filter mediainto a pleated configuration. The storing or creasing can occur as partof a continuous process wherein an edge is applied to the filter mediaacross the corrugations and wherein the direction of the creasealternates between pleat faces. In addition, the distance between thescoring or pleat faces represents the pleat height of the subsequentlyfolded pleated media pack.

The filtration media can be provided with a fine fiber material on oneor both sides thereof, for example, in accord with U.S. Pat. Nos.6,955,775, 6,673,136, and 7,270,693, incorporated herein by reference intheir entirety. In general, fine fiber can be referred to as polymerfine fiber (microfiber and nanofiber) and can be provided on the mediato improve filtration performance. As a result of the presence of finefiber on the media, it can be possible to provide media having a reducedweight or thickness while obtaining desired filtration properties.Accordingly, the presence of fine fiber on media can provide enhancedfiltration properties, provide for the use of thinner media, or both.Fiber characterized as fine fiber can have a diameter of about 0.001micron to about 10 microns, about 0.005 micron to about 5 microns, orabout 0.01 micron to about 0.5 micron. Exemplary materials that can beused to form the fine fibers include polyvinylidene chloride, polyvinylalcohol polymers, polyurethane, and co-polymers comprising variousnylons such as nylon 6, nylon 4,6, nylon 6,6, nylon 6,10, andco-polymers thereof, polyvinyl chloride, PVDC, polystyrene,polyacrylonitrile, PMMA, PVDF, polyamides, and mixtures thereof.

Several techniques can be relied upon for enhancing the performance ofpleated filtration media. The technique can be applied to pleatedfiltration media used in panel filter arrangements and for pleatedfiltration media used in closed loop filter arrangement. Depending onwhether the pleated filtration media is intended to be used in a panelfilter arrangement or a closed loop filter arrangement, alternativepreferences can be provided. In view of this disclosure, one wouldunderstand when certain preferences are more desirable for a panelfilter arrangement and when certain preferences are more desirable for aclosed loop filter arrangement.

Accordingly, it should be understood that the identification of apreference is not intended to reflect a preference for both panel filterarrangements and closed loop filter arrangements. Furthermore, it shouldbe understood that the preferences may change as a result of whether thefilter arrangement is intended to be an arrangement that can becharacterized as a forward flow arrangement (where dirty air flows intothe filter media pack from the exterior cylindrical surface) or areverse flow filtration media pack (where dirty flows into thefiltration media pack from the inner surface of the filtration mediapack).

Filter Elements

The following filter elements are provided as examples constructed inaccordance with the present invention, and are not intended to be allinclusive of element designs made in accordance with the teachingsherein. Rather, one of skill in the art will appreciate that variousalternative elements can be constructed while still within the scope ofthe disclosure and claims. In FIG. 14, a panel filter 300 is depicted.The panel filter 300 comprises filter media 301, pleated in aconfiguration comprising pleat folds 302. The panel 300 depictedincludes a frame construction 310 having a seal arrangement 312 thereon.The seal arrangement 312 is generally configured to form a seal with ahousing or other structure in which the panel filter 300 is positioned.The panel filter 300 also includes a support grid 314, across onesurface of the panel filter arrangement 300.

While there are variations in panel filters from those shown in FIG. 14,in general the features are analogous, comprising: a plurality ofparallel pleats; a seal arrangement secured within the panel filter;and, a rectangular configuration with one set of pleat folds 316 in aplane and the second set of pleat folds 318 in a separate plane. Ends oropposite edges 320 of the pleats can be closed by sealant, or by beingencased in a mold or frame, if desired. Although not depicted in FIG.14, plurality of the corrugations in the pleated media will often runsubstantially perpendicular to pleat folds 316 and 318 (although othernon-perpendicular directions are also envisioned). Thus, the pluralityof corruptions can extend in a direction from pleat folds 316 to pleatfolds 318.

In other arrangements, the pleated media is configured or arrangedaround an open central area. An example of such a filter arrangement isdepicted in FIGS. 15 and 16. Referring to FIG. 15, a filter arrangement330 is depicted. The filter arrangement 330 comprises first and secondend caps 332 and 334 having pleated media 336 extending therebetween.The pleats of the pleated media 336 generally extend in a directionbetween the end caps 332 and 334. The particular filter arrangement 330of FIG. 15 has an outer liner 340, shown broken away at one location,for viewing pleats. Typically, although pleats can be viewed through theliner 340, the arrangement 330 is simply not drawn that way, forconvenience. The outer liner 340 shown comprises expanded metal,although a variety of alternative outer liners, including plastic ones,can be used. In some instances, an outer liner is simply not used.Attention is also directed to FIG. 16, which is a side elevational viewof arrangement 330, showing end caps 332 and 334. Pleat folds 336 areshown, as is outer liner 340. For the particular arrangement 330 of FIG.15, a direction perpendicular to the pleat direction is generally acircumference of the filter arrangement 330, indicated by the doubleheaded arrow 342.

The particular filter arrangement 330 depicted is generally cylindrical,although alternatives are possible. Typically, such elements as element330 have an open end cap, in this instance corresponding to end cap 332,and a closed end cap, in this instance corresponding to end cap 334,although alternatives are possible. The term “open” when used inreference to an end cap, is meant to refer to an end cap which has anopen central aperture 344 to allow air flow between an interior space346 of the filter arrangement 330 and the exterior, without passagethrough the media 336. A closed end cap, by comparison, is an end capwhich has no aperture therein. Although not depicted, flutes willtypically be arranged in a direction from outer pleat folds of thepleated media 336 perpendicularly (or near perpendicularly) into theinterior of the element toward the inner volume 346. However, it will beunderstood that the flutes do not have to run perpendicular to the outerpleat folds.

A variety of arrangements have been developed for end caps 332 and 334.The end caps may comprise polymeric material molded to the media.Alternatively they may comprise metal end caps or other preformed endcaps secured to the media, with an appropriate adhesive or pottingagent. The particular depicted end caps 332 and 334 are molded end caps,each comprising compressible foamed polyurethane. End cap 332 is shownwith a housing seal 350, for sealing the element 330 in a housing duringuse. The depicted seal 350 is an inside radial seal, although outsideradial seals and axial seals are also possible.

It is noted that the element may include an inner liner 352 extendingbetween end caps 332 and 334 along an inside of the media 330 as shownin FIG. 15, although in some arrangements such liners are optional. Theinside liner, if used, can be metal, such as expanded metal orperforated metal, or it can be plastic.

The distance between the outside cylindrical surface and the insidecylindrical surface, defined by outer and inner pleat folds, isgenerally referenced as the pleat depth.

An arrangement such as that depicted in FIGS. 15 and 16 are sometimesreferenced herein as a “cylindrical arrangement,” using “cylindricallyconfigured” media, or by similar characterizations. Not all filterarrangements that utilize a closed loop configuration or tubularconfiguration are arranged as cylinders. An example of this isillustrated in FIG. 13. Referring to FIG. 17, a filter arrangement 400comprises extension of media 402 which is pleated, with pleat directionextending in the directions of arrow 404. Filter arrangement 400 issomewhat conical having a wide end 406 and a narrow end 408. At wide end406 is positioned an end cap 407, and at narrow end 408 is positioned anend cap 409. As with the cylindrical arrangement, a variety of open andclosed end caps can be used. For the specific example depicted, end cap407 is open and end cap 408 is closed.

Filter arrangement 400 includes outer support screen 410 extendingbetween end cap 407 and 409. The particular arrangement 400 includes noinner support screen although one could be used. The filter element 400includes a seal arrangement 412, in this instance an axial seal,although an inside or outside radial seal is possible. Element 400includes a non-continuously threaded mounting arrangement, 414, formounting a housing. The arrangement 400 is generally described in detailin PCT/US2003/33952 filed Oct. 23, 2003, incorporated herein byreference.

Now referring to FIGS. 18 and 19, a filter arrangement is shown asreference number 500. The filter arrangement 500 can be considered to bea type of conical filter element and/or a type of panel filter element.The filter element 500 is shown having a first face 502 and a secondface 504, with pleated media 506 extending between the first face 502and the second face 504. Corrugations constructed in accordance with thediscussion herein will typically be arranged directionally between thefirst and second faces 502, 504. The first face 502 includes a screen503, and the second face 504 includes a screen 505. The filter element500 includes a first side 510, second side 512, first end 514, andsecond end 516. The first side 510 and the second side 512 include apotting material 520 that help seals the sides of the pleated media 506,and a seal 522 that prevents fluid from bypassing the media 506 when theelement 500 is arranged in an air cleaner. The first end 514 and thesecond end 516 seal the ends of the pleated media faces, and includeguide pins 530 that help align the element 500 within the air cleaner.

The filter element 500 shown can be considered conical because theradius R1 is different than the radius R2. In general, the radius R1refers to the radius at the first side 510 and the radius R2 refers tothe radius at the second side 512. Although the filter element 500 isshown having a conical structure, it is possible for the radiuses R1 andR2 to be the same so that the filter element more closely resembles apartial cylindrical arrangement or, alternatively, as a bowed panelarrangement.

The filter elements can be utilized in various housing arrangements, andthe filter elements can be replaced or cleaned or refurbishedperiodically, as desired. In the case of air filtration, the housing canbe provided as part of an air cleaner for various air cleaning orprocessing applications including engine air intake, turbine intake,dust collection, and heating and air conditioning. In the case of liquidfiltration, the housing can be part of a liquid cleaner for cleaning orprocessing, for example, water, oil, fuel, and hydraulic fluid.

The principles, techniques, and features describes herein can be appliedin a variety of systems, and there is no requirement that all of theadvantageous features identified be incorporated in an assembly, system,or component to obtain some benefit according to the present disclosure.

Some Selected Final Characterizations

In this summary, some selected, final summary characterizations of theteachings herein are provided. Some selected, final summarycharacterizations include:

1. Filter media comprising:(a) a filtration substrate having a first side and a second side, andconstructed for filtering a fluid by flow of the fluid therethrough fromthe first side to the second side or from the second side to the firstside;(b) the filtration substrate has a first edge and a second edge, and afirst end and a second end, wherein the filtration substrate has amachine direction extending from the first end to the second end, and across direction extending from the first side to the second side;(c) the filtration substrate comprising a plurality of corrugationslocated in the cross direction and extending in the machine direction;(d) the plurality of corrugations comprising a plurality of first crestsformed along the first side of the filtration substrate and a pluralityof second crests formed along the second side of the filtrationsubstrate; and(e) the filtration substrate comprises a plurality of bosses locatedalong the plurality of first crests or along the plurality of secondcrests and extending in a direction away from the other of the pluralityof first crests or the plurality of second crests.2. Filter media according to characterization 1, wherein the filtermedia is arranged in a roll wound along the machine direction.3. Filter media according to characterization 2, wherein the filtermedia in a roll is arranged around a core and covered by a wrapper.4. Filter media according to any one of characterizations 1-3, whereinthe filter media comprises cellulosic media and has a basis weight ofabout 48 lb/3,000 ft² to about 75 lb/3,000 ft².5. Filter media according to any one of characterizations 1-4, whereinthe plurality of bosses comprise a result of embossing the filtrationsubstrate.6. Filter media according to any one of characterizations 1-5, whereinthe plurality of bosses have a height of at least about 5 mils.7. Filter media according to any one of characterizations 1-6, whereinthe plurality of bosses have a height of about 5 mils to about 50 mils.8. Filter media according to any one of characterizations 1-7, whereinthe plurality of bosses comprise adjacent bosses spaced apart by adistance of at least 50 mils between bosses.9. Filter media according to any one of characterizations 1-8, whereinthe plurality of bosses comprise adjacent bosses spaced apart along acommon crest by a distance of about 50 mils to about 1,500 mils.10. Filter media according to any one of characterizations 1-9, whereinthe plurality of bosses comprise a plurality of first bosses locatedalong the plurality of first crests and extending in a direction awayfrom the plurality of second crests, and a plurality of second bosseslocated along the plurality of second crests and extending in adirection away from the plurality of first crests.11. Filter media according to characterization 10, wherein thefiltration substrate comprises a plurality of creases wherein eachcrease separates alternating first and second pleat faces.12. Filter media according to characterization 11, wherein the pluralityof first bosses are located in the first pleat faces and not in thesecond pleat faces, and the plurality of second bosses are located inthe second pleat faces and not in the first pleat faces.13. Filter media according to any one of characterizations 1-12, whereinthe plurality of corrugations form a pattern of alternating first arcsand second arcs along the transverse direction, wherein the first arcsand the second arcs arc in opposite directions, and wherein the firstcrests are located at the peaks of the first arcs and the second crestsare located at the peaks of the second arcs.14. Filter media according to characterization 13, wherein the pluralityof corrugations are an asymmetric and the first arcs and the second arcshave different curvatures.15. Filter media according to characterization 13, wherein the pluralityof corruptions are symmetric, and the first arcs and the second arcshave curvatures that are similar.16. Filter media according to characterization 13, wherein the firstarcs and the second arcs have an amplitude of about 5 mils to about1,500 mils.17. Filter media according to any one of characterizations 1-16, whereinthe plurality of bosses comprise conical sides and rounded tops.18. Filter media according to any one of characterizations 1-17, whereinthe plurality of bosses comprise a spherical shape.19. Filter media according to any one of characterizations 1-18, whereinthe plurality of bosses have base perimeter of about 10 mils to about 60mils.20. A filter media pack comprising:(a) filter media provided in a pleated configuration comprisingalternating first and second pleat tips and alternating first and secondpleat faces, wherein:(i) the filter media includes a first edge and a second edge, and awidth extending from the first edge to the second edge;(ii) the filter media includes a first end and a second end, and alength extending from the first end to the second end; and(iii) the alternating first and the second pleat tips and thealternating first and second pleat faces are located along the length ofthe filter media;(b) the filter media comprises a plurality of corrugations arrangedacross the width of the media pack and extending along the length of thefilter media, wherein:(i) the plurality of corrugations comprise alternating first arcs andsecond arcs;(ii) the first arcs and the second arcs arc in opposite directions;(iii) each of the first arcs comprise a first crest and each of thesecond arcs comprise a second crest; and(c) the filter media comprises a plurality of bosses located along thefirst crest of the first arcs or along the second crest of the secondarcs so that the bosses extend in direction away from the other of thefirst crest or the second crest.21. A filter media pack according to characterization 20, wherein theplurality of bosses have a height sufficient to separate the alternatingfirst and second pleat faces when provided in the pleated configuration.22. A filter media pack according to any one of characterizations 20-21,wherein the media pack has a pleat density of about 6 pleats per inch toabout 16 pleats per inch.23. A filter media pack according to any one of characterizations 20-22,wherein the media pack has a pleat depth of at least about 0.375 inch,wherein the pleat depth is the longest distance from the first pleattips to the second pleat tips.24. Filter media pack according to any one of characterizations 20-23,wherein the plurality of bosses have a height of at least about 5 mils.25. Filter media pack according to any one of characterizations 20-24,wherein the plurality of bosses have a height of about 5 mils to about50 mils.26. Filter media pack according to any one of characterizations 20-25,wherein the plurality of bosses comprise adjacent bosses spaced apart bya distance of at least 50 mils between bosses.27. Filter media pack according to any one of characterizations 20-26,wherein the plurality of bosses comprise adjacent bosses spaced apartalong a common crest by a distance of about 50 mils to about 1,500 mils.28. Filter media pack according to any one of characterizations 20-27,wherein the plurality of bosses comprise a plurality of first bosseslocated along the plurality of first crests and extending in a directionaway from the plurality of second crests, and a plurality of secondbosses located along the plurality of second crests and extending in adirection away from the plurality of first crests.29. Filter media pack according to characterization 28, wherein theplurality of first bosses are located in the first pleat faces and notin the second pleat faces, and the plurality of second bosses arelocated in the second pleat faces and not in the first pleat faces.30. Filter media pack according to any one of characterizations 20-29,wherein the plurality of corrugations are asymmetric, and the first arcsand the second arcs have different curvatures.31. Filter media pack according to any one of characterizations 20-30,wherein the plurality of corruptions are symmetrical, and the first arcsand the second arcs have curvatures that are similar.32. Filter media pack according to any one of characterizations 20-31,wherein the first arcs and the second arcs have an amplitude of about 5mils to about 1,500 mils.33. Filter media according to any one of characterizations 20-32,wherein the plurality of bosses comprise conical sides and rounded tops.34. Filter media pack according to any one of characterizations 20-33,wherein the plurality of bosses comprise a spherical shape.35. Filter media according to any one of characterizations 20-34,wherein the plurality of bosses have base perimeter of about 10 mils toabout 60 mils.36. A method of forming a filter cartridge comprising:(a) forming a filter media pack by folding a filter media according toany one of characterizations 1-35 to form alternating first pleat tipsand second pleat tips; and(b) providing a seal member to prevent fluid to be filtered frombypassing the filter media pack.37. A method according to characterization 36, further comprising:(a) forming the filter media pack into a panel media pack.38. A method according to any one of characterizations 36-37, furthercomprising:(a) forming the filter media pack into a cylindrical media pack.39. A method according to any one of characterizations 36-38, furthercomprising:(a) forming the filter media pack into a conical media pack.

The above specification provides a complete description of themanufacture and use of the composition of the invention. Since manyembodiments of the invention can be made without departing from thespirit and scope of the invention, the invention resides in the claimshereinafter appended.

What is claimed is:
 1. Filter media comprising: (a) a filtration substrate having a first side and a second side, and constructed for filtering a fluid by flow of the fluid therethrough from the first side to the second side or from the second side to the first side; (b) the filtration substrate has a first edge and a second edge, and a first end and a second end, wherein the filtration substrate has a machine direction extending from the first end to the second end, and a cross direction extending from the first edge to the second edge; (c) the filtration substrate comprising a plurality of corrugations located in the cross direction and extending in the machine direction; (d) the plurality of corrugations comprising a plurality of first crests formed along the first side of the filtration substrate and a plurality of second crests formed along the second side of the filtration substrate; and (e) the filtration substrate comprises a plurality of bosses located along the plurality of first crests or along the plurality of second crests and extending in a direction away from the other of the plurality of first crests or the plurality of second crests.
 2. Filter media according to claim 1, wherein the filter media is arranged in a roll wound along the machine direction.
 3. Filter media according to claim 2, wherein the filter media in a roll is arranged around a core and covered by a wrapper.
 4. Filter media according to claim 1, wherein the filter media comprises cellulosic media and has a basis weight of about 48 lb/3,000 ft² to about 75 lb/3,000 ft².
 5. Filter media according to claim 1, wherein the plurality of bosses comprise a result of embossing the filtration substrate.
 6. Filter media according to claim 1, wherein the plurality of bosses have a height of at least about 5 mils.
 7. Filter media according to claim 1, wherein the plurality of bosses have a height of about 5 mils to about 50 mils.
 8. Filter media according to claim 1, wherein the plurality of bosses comprise adjacent bosses spaced apart by a distance of at least 50 mils between bosses.
 9. Filter media according to claim 1, wherein the plurality of bosses comprise adjacent bosses spaced apart along a common crest by a distance of about 50 mils to about 1,500 mils.
 10. Filter media according to claim 1, wherein the plurality of bosses comprise a plurality of first bosses located along the plurality of first crests and extending in a direction away from the plurality of second crests, and a plurality of second bosses located along the plurality of second crests and extending in a direction away from the plurality of first crests.
 11. Filter media according claim 10, wherein the filtration substrate comprises a plurality of creases wherein each crease separates alternating first and second pleat faces.
 12. Filter media according claim 11, wherein the plurality of first bosses are located in the first pleat faces and not in the second pleat faces, and the plurality of second bosses are located in the second pleat faces and not in the first pleat faces.
 13. Filter media according to claim 1, wherein the plurality of corrugations form a pattern of alternating first arcs and second arcs along the transverse direction, wherein the first arcs and the second arcs arc in opposite directions, and wherein the first crests are located at the peaks of the first arcs and the second crests are located at the peaks of the second arcs.
 14. Filter media according claim 13, wherein the plurality of corrugations are asymmetric, and the first arcs and the second arcs have different curvatures.
 15. Filter media according claim 13, wherein the plurality of corruptions are symmetric, and the first arcs and the second arcs have curvatures that are similar.
 16. Filter media according to claim 13, wherein the first arcs and the second arcs have an amplitude of about 5 mils to about 1,500 mils.
 17. Filter media according to claim 1, wherein the plurality of bosses comprise conical sides and rounded tops.
 18. Filter media according to claim 1, wherein the plurality of bosses comprise a spherical shape.
 19. Filter media according to claim 1, wherein the plurality of bosses have base perimeter of about 10 mils to about 60 mils. 